1. Field of the Invention
The invention is related to the field of communication networks and, in particular, to charging and billing in communication networks.
2. Statement of the Problem
When a phone call is placed over a communication network, there may be multiple entities that share in the revenue received for the call. For instance, the network operator that actually operates and maintains the network over which the call is placed shares in the revenue. If the call extends to a foreign communication network, such as for an international call, then the network operator of the foreign communication network shares in the revenue for the call. If a call extends to a roaming mobile user, then the network operator of the mobile network in which the user is roaming shares in the revenue. The process of determining which entities share in the revenue of a call is sometimes referred to as mediation.
In traditional communication networks, charging functions for calls are performed by network components, such as switches. Switches collect charging data for the calls, and generate Charging Detail Records (CDR) that include the charging data. Switches all over the entire network forward the CDRs to a billing system in service provider's IT system (often referred to as a back-end or back-office billing system). The back-office billing system stores information that may be used for the mediation process. For example, the billing system stores agreements that a network operator may have with a foreign network operator for international calls, stores agreements that a network operator may have with mobile networks for roaming scenarios, etc. The billing system also performs settlement processes to invoice customers for the telephone services, and to provide vouchers or credits to other entities.
In more recent charging architectures, postpaid charging is implemented through an Offline Charging System (OFCS) and an associated billing system. Similarly, prepaid charging is implemented through an Online Charging System (OCS) and an associated billing system. To provide offline and online charging, the OCS and the billing systems each maintain their own rating engine. Also, the billing systems each maintain profiles for the subscribers, profiles for the wholesale customers, and profiles for other network operators having contractual agreements. The overlap of the rating engines and the profiles wastes significant resources in the network. Operational inefficiencies and technical overhead for maintaining two separate charging systems may lead to the drawback in marketing and business activities for a network operator. Presently, the network operators are subject to great pressures to reduce the operational costs.